Benetton have sacked two key members of their technical staff saying it is time the team's potential is turned into results.

Team co-ordinator Joan Viladeprat and design chief Nick Whirth, who will be replaced by Tim Densham, have both left the camp.

Benetton said they wanted to improve the team's technical structure and that the new recruits would play a significant role in preparations for their challenge this season.

'Technological potential'

"We've had the technological potential for some time, even if this hasn't translated into results," said owner said Rocco Benetton.

"In the past year many things have changed in the sport but one of the most obvious things that came to my eye was that there was a need for changes in the team and I have implemented these changes."

Last season Benetton lagged behind the pace of their rivals in Ferrari, McLaren, Jordan and Williams but it is apparently the technicians, not the drivers, who have taken the blame.

Drivers Giancarlo Fisichella and Alexander Wurz remain for their third season with the Italian outfit.

"They are two young drivers of great talent whom we have trained carefully. Now they must start to reap the benefits of this work," said Benetton.

New test driver

Japanese driver Hideroshi Mitsusada, placed third last year in the Japanese Formula One championship, was named as Benetton's new reserve driver.

The 29-year-old, who comes from Osaka, finished third in last year's Formula Nippon championship with two race wins and one pole position and will be competing in Formula 3000 this season.

The 1995 world champions have been sliding steadily down the constructors' rankings in recent seasons, from third place in 1997 to fifth in 1998 and a disappointing sixth at the end of last year with just 16 points.

Fisichella provided the bulk of the points, 13 in all, after finishing second in Canada.